(1) Field of the Invention
The present invention relates to a connector for use in connection of electric wires and so on, in particular, a connector including: a housing for receiving a terminal fitting attached to an end of an electric wire; and a seal body to maintain a watertight characteristic between an inner surface of the housing and the electric wire.
(2) Description of the Related Art
Various electronic instruments are mounted on a motor vehicle as a mobile unit. The motor vehicle mounts a wiring harness for transmitting electric power and control signals to the electronic instruments. The wiring harness includes a plurality of electric wires and connectors.
As shown in FIG. 9, a connector 100 including: a connector housing 103 for receiving terminal fittings 102, attached to ends of electric wires 101; and a seal member 104 to maintain a watertight characteristic between an inner surface of the connector housing 103 and outer surfaces of the electric wires 101 is known (see Japanese Patent Application Laid-Open No. 2000-323229).
The seal member 104 is made of resilient material such as rubber and constructed with a pair of seal bodies 105 and 106, which puts the electric wire 101 therebetween. One end of the seal body 105 and one end of the seal body 106 are connected by a hinge 107. As shown in FIGS. 9 and 10, each seal body 105, 106 has a plurality of grooves 108 each formed in a semi-circle-shape in cross section. The grooves 108 are lined up in parallel to each other. The electric wire 101 is positioned within the grooves 108.
Each seal body 105, 106 is provided with a lip part 110 which projects from an inner surface of the groove 108 toward the inside of the groove 108 in a diameter direction thereof. Because the lip part 110 resiliently comes in contact with an outer periphery of the electric wire 101, therefore the watertight characteristic between the electric wires 101 and inner surfaces of the pair of the seal bodies 105, 106 is maintained. The seal member 104 is press-fit into the connector housing 103 on a condition that the electric wires 101 are placed between the pair of the seal bodies 105 and 106.
As for the seal member 104 of the connector 100, the thickness of the lip part 110 is formed identical throughout the entire region of the lip part 110. That is, the thickness S1 of the lip part 110 in the proximity of an abutting surface 111 between the seal bodies 105 and 106 is formed identical to the thickness 32 of the lip part 110 at a bottom part 112 of the groove 108 being farthest away from the abutting surface 111. In such a construction, because a portion of the lip part 110 near the abutting surface 111 is less resilient than a portion of the lip part 110 at the bottom part 112 of the groove 108, there is a problem in that contact pressure, that is, a sealing characteristic of the lip part 110 against the electric wire 101 in the proximity of the abutting surface 111 becomes small and ineffective.
Moreover, as for the seal member 104, depending on its attaching condition to the connector 100 and size dispersion of the seal member 104, as shown in FIG. 11, there is a problem that a working pitch of the grooves 108 between the seal bodies 105 and 106 might be undesirably displaced. In this case, because the abutting surface 111 positioned in between the grooves 108 adjacent to each other has a small width and low mechanical strength, the abutting surface 111 of the seal body 105, 106 does not abut against an abutting surface 111 of the mating seal body 105, 106 and as shown in FIG. 12, the abutting surface 111 might be undesirably turned up, causing a problem that the sealing characteristic between the abutting surfaces 111 becomes inferior.